The present invention relates to security vaults and more particularly, to an improved modular vault panel.
In the past, vaults for storing safety deposit boxes and reserve money were constructed of poured concrete walls approximately 18-36 inches thick and were very difficult and expensive to construct in a new bank structure. The time required to erect concrete forms, install the reinforcing materials, pour the concrete, strip the forms and let the concrete cure added significant time and cost to the construction of new bank structures. Further, that process made the installation of a vault almost impossible in an existing building.
A number of years ago, regulatory authorities specified the construction of a vault wall for a particular application. However, over the last 25 years, rather than specifying a particular construction, the regulatory authorities now specify only the burglary resistance of a vault as set forth in Underwriters Laboratories, Inc. Specification for Vaults UL 608. The UL 608 specification classifies the burglary resistance of a vault according to the length of time the vault is able to withstand an attack by common burglary tools. For example, class M vaults resist attack for one-quarter an hour, class 1 vaults for one-half an hour, class 2 vaults for one hour and class 3 vaults for two hours. Once a vault classification has been established for a particular application, vault manufacturers are able to use any construction that meets the burglary resistance UL certification requirements of the classification. Therefore, manufacturers of vaults now compete to provide more efficient and effective constructions that meet the particular specifications of a class of vault.
A major improvement and cost savings in vault construction over the past 25 years is the use of prefabricated concrete panels. Such panels are manufactured off-site by the vault manufacturer, shipped to the bank building construction site and assembled into a floor, walls and ceiling of a finished vault. The use of such panels to construct a vault is substantially more efficient, less costly and easier than the earlier on-site poured concrete constructions. The modular vault construction has the further advantage of being easily disassembled and moved to another facility if the bank business moves.
As will be appreciated, the design of the specific structure of a prefabricated concrete panel is directed to a particular market represented by one of the vault classifications in the UL specification. In order to be competitive within that market, there is a continuing effort to reduce vault panel costs while maintaining a structural integrity to meet the specifications of the desired UL class. All of the prefabricated concrete panels are constructed of a reinforced high compression strength concrete. The design of the reinforcing, the composition of the concrete and other elements will vary depending on the vault manufacturer; however, generally, prefabricated concrete panels that meet a class 1 UL specification are at least six inches thick.
Thus, there is a continuing need to make the construction of the reinforced concrete panel more economical without reducing its resistance to burglary.
The present invention provides an improved modular concrete panel for a vault that is smaller and lighter than comparable panels having the same resistance to burglary. Further, the panel is less expensive to manufacture, less expensive to transport and easier to handle during the construction process. Thus, the modular concrete panel of the present invention is particularly well suited for installation in existing structures and has the further advantage of being able to be disassembled and moved to another location.
In accordance with the principles of the present invention and the described embodiments, the invention provides a modular concrete vault panel including two opposed metal side rails and two opposed metal end rails having ends rigidly connected to ends of the side rails to form a metal rectangular frame. A rebar lattice is supported within the frame, and waveform rebar extends longitudinally within the frame. The frame is then filled with a high compression strength concrete to produce the modular concrete vault panel.
In one aspect of the invention, the rebar lattice has a pair of lateral rebar rods and a pair of waveform rebars, each of the lateral rebar rods extends adjacent one of the side rails and one of the waveform rebars is rigidly connected to one of the lateral rebar rods.
In another embodiment, the above-described modular concrete panel further includes a second pair of opposed metal side walls and a second pair of opposed metal end walls having ends rigidly connected to ends of the second side walls to form a second rectangular metal frame. A second rebar lattice is supported within the second frame, and a ventilation channel extends through the two frames.
The above and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof.